DE 29 32 105 A1 describes an inking unit for an offset rotary printing press having two roller trains, three forme rollers, and a roller stand. The roller stand is displaceably disposed such that a distribution roller is either engaged against a third forme roller or is separated from the third forme roller during operation of the printing press.
In modern offset printing presses, inking units of printing couples are ordinarily equipped with washing devices that are operable to allow the inking unit to be cleaned as needed. To allow dampening units to also be washed in such printing presses, both the ink forme rollers and the dampening forme roller must be engaged against the plate cylinder. This will allow washing solution to be transferred from the inking unit onto the dampening unit. It is also necessary for the plate cylinder to be fully loaded with plates during such a washing procedure. During a production run involving a partially loaded plate cylinder, the missing plates must therefore be mounted onto the plate cylinder solely for the purpose of washing the dampening unit. This requirement and procedure is both inconvenient and time-consuming.
WO 2004/054804 A1 and WO 2005/007409 A2 both describe inking and dampening units with displaceable stripper rollers.
DE 10 2005 056 812 A1, DE 19 32 642 U and DE 40 12 283 A1 all disclose intermediate rollers that can be moved for washing.
U.S. Pat. No. 3,701,316 A and U.S. Pat. No. 4,036,131 A each disclose an inking unit and a dampening unit. A dampening forme roller can be engaged against an ink forme roller for the purpose of washing.